Insects and Flowers 
5 6 3 
cf plant-feeding insects, the leaf-eating beetles and locusts and caterpillars, 
the sap-sucking bugs and plant-lice, the plant furnishes food alone; and 
in furnishing it, under a rough compulsion, is nearly always the loser, even, 
often enough, to death. The special relation between insects and plants 
to which this chapter is devoted is also a kind of food relation, but with the 
unusual character of being one in 
which the plant is not at all a loser 
but a gainer, and in as great measure 
as the insect itself. Only plants with 
flowers and mostly only those with 
bright-colored, odorous, and nectar- 
secreting flowers, have any part in 
this relation, which is, as the reader 
has already recognized, that interest¬ 
ing phenomenon, the cross-pollination 
of flowers by their insect visitors. 
As this interrelation of flowers and 
insects is one of very large importance 
in the life of many insect kinds, pro¬ 
found modifications of their structure 
and habits depending on it, and as 
popular knowledge of the subject is 
likely to be extremely general in its 
scope, I have thought it advisable to 
present a brief special account of this 
phenomenon. 
The agency of insects in effecting 
the cross-pollination of flowers has 
long been recognized. Credit is given to 
Sprengel for first publishing accounts 
of the interesting modifications of 
flowers due to their interrelation with 
insects, and for discovering that the 
insects were instrumental in pollinating 
the flowers. (Das entdeckte Geheim- 
niss der Natur im Bau und in der 
Befruchtung der Blumen, von Chris¬ 
tian Konrad Sprengel, Berlin, 1793). 
But that this pollination by insects was (nearly) exclusively cross-pollination 
he did not apparently fully understand, or at least he did not fully under¬ 
stand the significance of cross-pollination. It was reserved for Darwin 
(On the Fertilization of Orchids by Insects, London, 1862), on a basis not 
Fig. 760 —Snapdragon being visited by 
honey-bees. (From nature.) 
